Integrative taxonomy and phylogenetic systematics of the Triatoma rubrovaria subcomplex (Hemiptera, Triatominae).

Triatoma rubrovaria subcomplex consists of T. carcavalloi, T. circummaculata, T. klugi, T. limai, T. oliveirai, T. pintodiasi, T. rubrovaria, T. patagonica and T. guasayana, which can be vectors of Trypanosoma cruzi, the etiologic agent of Chagas disease. In this study, morphological, morphometric, and genetic characters of T. circummaculata, T. pintodiasi, T. carcavalloi, T. klugi, and T. rubrovaria were analyzed in view of the integrative taxonomy and phylogeny of the T. rubrovaria subcomplex. Molecular studies were carried out through the sequencing and analysis of the mitochondrial genes COI and CytB, nuclear genes ITS I, ITS 2, 16S, and 28S from rDNA and rescued a monophyletic group. Furthermore, differential morphological characters were found among the five species in the pronotum, scutellum, stridulatory sulcus, male genitalia, and external female genitalia. Finally, morphometric analyses made it possible to differentiate the five species. Phylogenetic analyzes rescued the relationship of T. pintodiasi with members of the T. rubrovaria subcomplex and demonstrated that this subcomplex is a monophyletic group composed of the species T. carcavalloi, T. circummaculata, T. klugi, T. guasayana, T. limai, T. oliveirai, T. patagonica, T. pintodiasi, and T. rubrovaria. Furthermore, through integrative taxonomy, it was possible to confirm the specific status of the species T. carcavalloi, T. circummaculata, T. pintodiasi, T. klugi, and T. rubrovaria, offering new useful morphological characters for the differentiation and characterization of these potential vectors and distributed in Southern Brazil.

Description of Rhodnius marabaensis sp. n. (Hemiptera, Reduviidae, Triatominae) from Pará State, Brazil.

Rhodnius marabaensissp. n. was collected on 12 May 2014 in the Murumurú Environmental Reserve in the city of Marabá, Pará State, Brazil. This study was based on previous consultation of morphological descriptions of 19 Rhodnius species and compared to the identification key for the genus Rhodnius. The examination included specimens from 18 Rhodnius species held in the Brazilian National and International Triatomine Taxonomy Reference Laboratory in the Oswaldo Cruz Institute in Rio de Janeiro, Brazil. The morphological characteristics of the head, thorax, abdomen, genitalia, and eggs have been determined. Rhodnius prolixus and Rhodnius robustus were examined in more detail because the BLAST analysis of a cyt-b sequence shows they are closely related to the new species, which also occurs in the northern region of Brazil. The most notable morphological features that distinguish Rhodnius marabaensissp. n. are the keel-shaped apex of the head, the length of the second segment of the antennae, the shapes of the prosternum, mesosternum and metasternum, the set of spots on the abdomen, the male genitalia, the posterior and ventral surfaces of the external female genitalia, and the morphological characteristics of the eggs. Rhodnius jacundaensis Serra, Serra & Von Atzingen (1980) nomen nudum specimens deposited at the Maraba Cultural Center Foundation - MCCF were examined and considered as a synonym of Rhodnius marabaensissp. n.

Mitochondrial Genes Reveal Triatoma jatai as a Sister Species to Triatoma costalimai (Reduviidae: Triatominae).

Triatoma jatai was described using a set of morphological structures from specimens collected in Paranã municipality of Tocantins State, Brazil. Under a Bayesian framework and using two mitochondrial genes (16S and COI), phylogenetic analysis recovered T. jatai as a sister species to Triatoma costalimai with higher genetic distances than between other well-recognized species. Our results agree with previous suggestions based on morphometric analysis. In the light of the non-monophyly of Matogrossensis subcomplex, the inclusion of T. jatai shall be considered for reevaluating this group.

Multiple mitochondrial genes of some sylvatic Brazilian Triatoma: non-monophyly of the T. brasiliensis subcomplex and the need for a generic revision in the Triatomini.

Multiple fragments of mitochondrial DNA genes (cytochrome b, cytochrome oxidase I, and 16S rDNA) were used to evaluate the phylogenetic relationships among Triatoma melanocephala, Triatoma tibiamaculata, Triatoma vitticeps, and other members of Triatoma brasiliensis subcomplex under a Bayesian framework and maximum parsimony criterion. With the addition of new sequences of T. tibiamaculata and T. vitticeps, Triatoma juazeirensis, Triatoma melanica and the newly sequenced T. melanocephala, the three first sylvatic species, T. melanocephala, T. tibiamaculata and T. vitticeps, were strongly recovered into a clade separate from the other with the remaining Triatoma species from South America, such as the members of T. brasiliensis subcomplex. Panstrongylus megistus was recovered as a sister to T. tibiamaculata, whereas T. vitticeps was a sister to T. melanocephala. This study revealed the non-monophyly of the T. brasiliensis subcomplex, and the polyphyly of Triatoma was reinforced by the placement of these three sylvatic species with Dipetalogaster, Meccus, Mepraia, and Panstrongylus. The results herein shown highlight the need of generic revision in Triatomini.

Study of the external female genitalia of 14 Rhodnius species (Hemiptera, Reduviidae, Triatominae) using scanning electron microscopy.

BACKGROUND: Among the vectors of Chagas disease (Hemiptera: Reduviidae:Triatominae), there are eighteen Rhodnius species described and some are difficult to identify. The aim of this article is to contribute to the specific identification of fourteen Rhodnius spp. through morphological characters of the external female genitalia. METHODS: Female abdomens were cut transversely. The specimens were then prepared for examination by using scanning electron microscopy. RESULTS: The careful examination of the dorsal, posterior and ventral sides revealed characteristics that allowed the identification of each of the fourteen species. CONCLUSION: The use of external female genitalia as characteristics are proposed as a tool for specifically identifying Rhodnius species, and an identification key for these species is presented.

A novel association between Rhodnius neglectus and the Livistona australis palm tree in an urban center foreshadowing the risk of Chagas disease transmission by vectorial invasions in Monte Alto City, São Paulo, Brazil.

After several public notifications of domiciliary invasions, palm trees were investigated in downtown Monte Alto City, São Paulo State, Brazil, in proximity to the city hall building, the main church, condominiums and marketing establishments. One hundred seventy four palm trees of 10 species were investigated, in which 72 specimens of Rhodnius neglectus, a potential Chagas disease vector, were captured via manual methods. All insects were collected from dead leaves, organic debris and bird nests in the only three Livistona australis palm trees in the central park square. This was the first record of R. neglectus colonizing this palm species. Although no Trypanosoma cruzi was found by abdominal compression followed by light microscopy, the poor nutritional status of the bugs hampered the examination of gut contents for parasite detection. Furthermore, the central crowns of the trees, which shelter bats (Chiroptera: Mammalia), could not be carefully searched for insects due to difficult access. This new finding highlights the sudden alteration in insect behavior, probably as a result of man's interference. This report aims to warn those involved in the health system about this new threat, justifying detailed research of the area to evaluate the magnitude of this emerging public health issue.

Evolutionary relationships of the Triatoma matogrossensis subcomplex, the endemic triatoma in Central-Western Brazil, based on mitochondrial DNA sequences.

The phylogenetic relationships among species of Triatoma matogrossensis subcomplex (T. baratai, T. guazu, T. matogrossensis, T. sordida, T. vandae, and T. williami) was addressed by using fragments of cytochrome oxidase I (COI), 16S rDNA (16S), and cytochrome b (Cytb) through Bayesian and parsimony analyses. We did not recover a monophyletic T. matogrossensis subcomplex, and their members were found clustered in three strongly supported clades, as follows: i) T. jurbergi + T. matogrossensis + T. vandae + T. garciabesi + T. sordida; ii) with T. guasayana as the sister group of clade (i); and iii) T. williami + T. guazu, however not closely related to the clade formed by the previously mentioned species. The other two endemic species from Central-Western Brazil, T. baratai and T. costalimai, were not recovered with strong clade support as related to other members of this subcomplex. Results call for a further revision in the classification of the subcomplexes within the genus Triatoma.

Characterization of the external female genitalia of six species of Triatominae (Hemiptera: Reduviidade) by scanning electron microscopy.

By macroscopic and microscopic dorsal side observation, it was noted that the IX and X segments of two species each of Panstrongylus and Triatoma terminate in an elongated way, whereas they terminate abruptly in the two species of Rhodnius. Scanning observation of the dorsal, ventral, lateral and posterior sides of the female genitalia of Panstrongylus herreri, Panstrongylus megistus, Rhodnius colombiensis, Rhodnius prolixus, Triatoma infestans and Triatoma vitticeps revealed that these six species are generally and specifically distinguished based on these elements. We describe several components that distinguish P. herreri from P. megistus: four on the dorsal side: the VII, VIII, IX and X segments, on the ventral view, three: VII sternite, VIII gonocoxite and VIII gonapophyse, on the lateral view one character, VIII gonocoxite and on the posterior view three characters: VIII and IX gonocoxite and XI gonopophyse. Comparing R. colombiensis and R. prolixus, there were three distinct characters on the dorsal side: the VII, VIII and X segments, on the ventral view three characters: the IX and X segments and VIII gonocoxite and on the posterior view four characters: the VIII, IX, X segments and VIII gonapophyse that distinguish the two species. T. infestans and T. vitticeps have four different characters on the dorsal side: the VII, VIII, IX and X segments, on the ventral view four characters: the VII and X segments, VIII gonocoxite and VIII gonapophyse, on the lateral view two characters, IX and X segments and on the posterior view four characters: the IX and X segments, VIII gonocoxite and VIII gonapophyse that distinguish the two species. Examination of the external female genitalia of six triatomine species by scanning suggests that these components are useful for taxonomical studies.

Characterization of the external female genitalia of six species of Triatominae (Hemiptera: Reduviidade) by scanning electron microscopy

By macroscopic and microscopic dorsal side observation, it was noted that the IX and X segments of two species each of Panstrongylus and Triatoma terminate in an elongated way, whereas they terminate abruptly in the two species of Rhodnius. Scanning observation of the dorsal, ventral, lateral and posterior sides of the female genitalia of Panstrongylus herreri, Panstrongylus megistus, Rhodnius colombiensis, Rhodnius prolixus, Triatoma infestans and Triatoma vitticeps revealed that these six species are generally and specifically distinguished based on these elements. We describe several components that distinguish P. herreri from P. megistus: four on the dorsal side: the VII, VIII, IX and X segments, on the ventral view, three: VII sternite, VIII gonocoxite and VIII gonapophyse, on the lateral view one character, VIII gonocoxite and on the posterior view three characters: VIII and IX gonocoxite and XI gonopophyse. Comparing R. colombiensis and R. prolixus, there were three distinct characters on the dorsal side: the VII, VIII and X segments, on the ventral view three characters: the IX and X segments and VIII gonocoxite and on the posterior view four characters: the VIII, IX, X segments and VIII gonapophyse that distinguish the two species. T. infestans and T. vitticeps have four different characters on the dorsal side: the VII, VIII, IX and X segments, on the ventral view four characters: the VII and X segments, VIII gonocoxite and VIII gonapophyse, on the lateral view two characters, IX and X segments and on the posterior view four characters: the IX and X segments, VIII gonocoxite and VIII gonapophyse that distinguish the two species. Examination of the external female genitalia of six triatomine species by scanning suggests that these components are useful for taxonomical studies.